The present invention is related to the co-pending application of John Lindley Baugh and Melvin J. Hardy entitled "SETTING TOOL", filed July 6, 1982, Ser. No. 395,211.
The present invention relates generally to oil well setting tools of the type adapted for engaging a setting sleeve run on a pipe string into a well bore, and specifically to a setting tool which allows right hand torque to be used during well bore operations as well as right hand torque to release the setting tool from the setting sleeve.
Setting tools are used for various purposes during well drilling and completion operations. For instance, a setting tool is typically used during setting of a liner hanger in a well bore. The setting tool is made up in the pipe string between the liner hanger and the pipe string running to the well surface. The setting tool serves as a link to transmit torque to the liner hanger to hang the liner in the well bore. The setting tool is then typically manipulated from the well surface to effect a release of the setting tool from the liner hanger and the liner is then cemented into place in the well bore.
In a typical well drilling pipe string, the lengths of pipe are connected by tool joints with right hand threads which are released by left hand torque. Drilling is thus carried out by clockwise rotation of the drill string to avoid breaking out the tool joints making up the pipe string. In certain setting tool designs, connecting threads were used to engage the setting tool with the setting sleeve which were releasable by right hand torque on the pipe string from the surface. However, this necessitated holding left hand torque on the pipe string while running into the well bore and dictated that the liner be set to the left in order to avoid releasing the setting tool connecting threads. Because left hand torque was used to set the liner, the possibility existed that tool joints in the pipe string would be unscrewed and a joint broken out.
It is, therefore, preferred to utilize a setting tool which allows the liner to be set by applying right hand torque from the surface and which allows the setting tool to be released and pulled out of the well bore by applying a similar right hand torque. There exists a need, therefore, for a setting tool which will allow right hand torque to be used during setting of a liner hanger or similar tool which also allows right hand torque to be used to release the tool.
A need exists for such a setting tool which has a premature release feature which maintains the tool in a locked, running-in position until a predetermined load is placed on the tool to effect release of the tool.
A need also exists for such a tool which has a torque override feature which allows a predetermined torque load to override the locking mechanism to allow the setting tool to be released without applying a load to effect vertical motion of the tool within the well bore.
A need also exists for a tool which is preloaded in the locked position at all times in order to lessen the possibility of inadvertent release.